The importance of urine 5-hydroxyindoleacetic acid levels in the early diagnosis of acute appendicitis

Purpose

Acute appendicitis is one of the most common surgical emergencies. Diagnosis is usually made depending on the presenting history, clinical evaluation, and laboratory tests. The aim of this study was to investigate the role of urinary 5-hydroxyindoleacetic acid (U-5-HIAA) in the early diagnosis of acute appendicitis.

Methods

Thirty-five pigmented male rabbits were divided into 5 groups. Group 1 is the control (n = 7); group 2 is the sham (n = 10). The appendix was ligated from its base, and an appendectomy was performed after 12, 24, 36 hours in group 3 (n = 7), group 4 (n = 7), and group 5 (n = 7), respectively. Spot urine samples were obtained for U-5-HIAA determination, and appendectomy tissues were examined histopathologically.

Results

Acute appendicitis was diagnosed in all animals in group 3, group 4, and group 5, and the mean levels of U-5-HIAA in group 3 were higher than in the other groups. The mean of U-5-HIAA levels between animals with appendicitis and those without showed a significant difference (P = .003). The U-5-HIAA cutoff point of 4.15 mg/g creatinine had a sensitivity of 85%, a specificity of 64.29%, and an accuracy of 76% (area under curve = 0.805) for acute appendicitis. The probability of acute appendicitis is found to be 10, 2 times more when the U-5-HIAA level is greater than 4.15 mg/g creatinine.

Conclusion

We have concluded that spot U-5-HIAA level increases significantly in the early stages of acute appendicitis.     

Simultaneous liquid-chromatographic determination of urinary vanillylmandelic acid, homovanillic acid, and 5-hydroxyindoleacetic acid

We describe a liquid-chromatographic method for quantifying, simultaneously by a single procedure, vanillylmandelic acid (VMA), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) in urine. After solvent extraction of acidified urine, the analytes were chromatographed on a C8 column, with use of a mobile phase of phosphate buffer (20 mmol/L, pH 4.0) and methanol with a variable gradient elution, and detected fluorometrically. We report the analytical recovery, sensitivity, precision, working linear range, and potential for interference from similar molecules or drugs. The results of such tests demonstrate that the proposed method is sensitive and reproducible. It is, furthermore, easy to perform, and thus is suitable for use in the clinical laboratory.     

Daily cyclic changes in the urinary excretion of 5-hydroxyindoleacetic acid in patients with carcinoid tumors

BACKGROUND: Vasoactive peptides produced by neuroendocrine tumors can induce characteristic symptoms of the carcinoid syndrome (flushing, diarrhea, and wheezing). To what extent external factors provoke these symptoms and how excretion of 5-hydroxyindoleacetic acid (5-HIAA), the degradation product of serotonin, varies throughout the day remain unknown. In this study, we investigated whether symptoms and daily activity are related to 5-HIAA excretion and whether 24-h urine collection is needed. METHODS: In 26 patients with metastatic carcinoid (14 men and 12 women; median age, 60 years) urine was collected in portions of 4 or 8 h during 2 days. Patients were asked to keep a diary in which they noted symptoms of flushes, consistency of stools, activities, and food intake. RESULTS: Excretion of 5-HIAA in 24-h urine was increased in 88% of the patients (median, 515 micromol/24 h). Overnight-collected urine appeared the most representative for 24-h collection concentrations (correlation coefficient = 0.81). We found no clear correlation between symptoms of the carcinoid syndrome and degree of activity. Watery diarrhea was reported only by patients with strong variations in 5-HIAA excretion. One-half of the patients (n = 16) exhibited a high variability in urinary 5-HIAA excretion throughout the day, with increased concentrations most prominent in morning collections (P = 0.0074) and lower concentrations in the evening (P = 0.0034). In the other patients these curves were flat. CONCLUSIONS: Cyclic changes in patients relate to high variability in 5-HIAA excretion. Overnight-collected urine can replace the 24-h urine collection, and marked variations in 5-HIAA excretion seem to be associated with severity of diarrhea.     

Urinary 5-hydroxy indole acetic acid as a test for early diagnosis of acute appendicitis

OBJECTIVES: Acute appendicitis (AA) is the most common abdominal emergency. The appendix has abundant serotonin containing cells. Upon inflammation, serotonin is released in the blood and converted into 5-HIAA (5-hydroxy indole acetic acid). Measurement of the urine 5-HIAA (U-5-HIAA) could be a reliable marker of inflammation of the appendix. We have compared the powers of test performance of spot U-5-HIAA and spot U-5-HIAA/creatinin with other routine laboratory tests used for the diagnosis of acute appendicitis. DESIGN AND METHODS: Urine, serum, and blood samples of 110 patients who were admitted and observed in the emergency units of two university hospitals were studied. 5-HIAA was measured using HPLC, C-reactive protein by immunoturbidometry, WBC by electronic cell counting, and urine creatinine by the Jaffe method. Diagnostic accuracy of the various tests was evaluated by receiver operating characteristic (ROC) analysis. FINDINGS: The mean of spot U-5-HIAA in 39 patients with AA (nongangrenous) was 32 +/- 2.6 micromol/L, which was much higher than the mean of 40 non-appendicitis patients (NA) (5.5 +/- 0.6), 10 follicular hyperplasia (7.5 +/- 2.1), and 50 healthy control cases (4.1 +/- 0.5) with P < 0.001. The concentration of U-5-HIAA in 21 patients with gangrenous appendicitis (GA) (13.8 +/- 2.1) was also higher than NA patients and healthy individuals but lower than AA cases (P < 0.05). Considering 10 micromol/L as the cutoff point, this test shows 84% sensitivity and 88% specificity, with 90% and 81% positive and negative predictive values, respectively. The area under ROC curve (AUC) of U-5-HIAA in the diagnosis of AA (AUC = 0.903) was much larger than AUCs of U-5-HIAA/Cr (0.787), WBC (0.703), and CRP (0.660). CONCLUSION:: Urinary secretion of 5-HIAA increases significantly in acute appendicitis and measurement of spot U-5-HIAA gives higher diagnostic accuracy than other routine laboratory tests. While the inflammation progresses to necrosis of the appendix, the concentration of 5-HIAA decreases. This decrease could be a warning sign of perforation of the appendix.     

Observations on the specificity of the urinary 5-hydroxyindoleacetic acid determination with 1-nitroso-2-naphtol

Cardiac function during acute hyperglycaemia was investigated by means of echocardiography in eight insulin-dependent (type 1) diabetic patients without microvascular or cardiac disease. Blood glucose was raised from 5.1±0.8 to 13.0±0.9 mmol/l for 1 h and then to 20.1 + 1.2 mmol/l for 1 h. A saline control study was performed to obtain an equal amount of plasma volume expansion. The left ventricular end-diastolic diameter increased significantly in both studies, however, significantly more following glucose infusion (3.3% at blood glucose of 13.0 mmol/l, 5.4% at blood glucose of 20.1 mmol/l versus 2.7% after both saline infusions). At the blood glucose level of 20.1 mmol/l, fractional shortening of the left ventricle and cardiac output were increased as compared with the baseline level and the level during moderate hyperglycaemia, and also increased compared with values of non-diabetics. In conclusion acute hyperglycaemia is followed by increased myocardial performance, probably as a consequence of increased peripheral blood flow.     

便携式彩色多普勒超声在急性阑尾炎诊断中的价值

目的探讨便携式彩色多普勒超声在诊断急性阑尾炎中的临床应用与诊断价值。方法将227例下腹痛临床疑诊阑尾炎的患者分为两组，对照组接受普通超声检查，干预组接受便携式彩色多普勒超声检查，分别将两组超声诊断结果与手术病理结果比较后，对比分析两组相关数据。结果干预组超声诊断急性阑尾炎且进入手术88例，经病理证实84例，阳性符合率95．45％（84／88），误诊4例，误诊率4．55％（4／88），漏诊2例，漏诊率2．33％（2／86）；对照组超声诊断急性阑尾炎且进入手术86例，经病理证实80例，阳性符合率93．02％（80／86），误诊6例，误诊率6．98％（6／86），漏诊5例，漏诊率5．88％（5／85）。干预组平均候检时间1．5h，平均住院时间124h；对照组平均候检时间5．9h，平均住院时间147h。结论便携式彩超检查体积小巧，方便快捷，性能更佳，可以随时反复进行，及时发现早期病变，及时接受手术治疗，缩短住院时间和减少不良并发症，对于帮助临床医师提高早期诊断率，减少不良并发症有重要价值。     

高频超声对急性阑尾炎的诊断价值

目的为探讨高频超声对急性阑尾炎的诊断价值。方法回顾性分析101例经手术和（或）病理证实的急性阑尾炎。结果其声像图表现：①直接征象：阑尾不同程度肿大,阑尾纵切面显示为数厘米长的腊肠样、管状、手指状或蚯蚓状的低回声或无回声区,不均质。横断面呈“靶环征”或圆形回声;②间接征象：阑尾内粪石并声影;阑尾炎有渗出或穿孔时周围的无回声区或有沉积物回声;脓肿形成时为右下腹混合性肿块回声;肠管扩张（特别是升结肠扩张）;回盲部肠管局限性水肿或肠系膜增厚和大网膜包裹。结论超声检查简便、可重复性对急性阑尾炎诊断有很大的实用价值,应列为首选的影像检查方法。     

Sequential cytokine levels in the diagnosis of appendicitis

OBJECTIVE: To determine the diagnostic value of sequential white blood cell count (WBC), tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in patients with abdominal pain. MATERIAL AND METHODS: Tests were determined at hospital admission and 6 h later in 105 children. Patients who were non-operatively followed and had a normal histopathology were classified as the non-appendicitis (NA) group. Patients with symptoms consistent with appendicitis were classified as the appendicitis group (A). Data were analyzed as positive/negative predictive value, sensitivity, specificity and accuracy rate (AR). The global power of the variables in discriminating the patients between the two groups and advanced/simple appendicitis was assessed from the area under the receiver operating characteristic (ROC). RESULTS: Initial measurements showed WBC to be a valuable diagnostic tool in acute appendicitis (AR = 74 %), whereas IL-6 and TNF-alpha were found not to be valuable. The second measurements revealed higher values, and IL-6 reached its highest AR (89 %). When initial values were evaluated in combination, the highest AR of 73 % was observed with TNF-alpha + WBC. The highest AR (90 %) was seen with IL-6 + TNF-alpha in the second measurements. ROC analysis showed WBC to be the most valuable parameter of the three. The area under the curve (AUC) was 0.750 for the initial measurement and 0.779 for the repeat measurement of WBC (p = 0.001). The most useful diagnostic parameter in discriminating between the simple and the advanced cases was IL-6 as assessed with the ROC curve (p<0.01). CONCLUSIONS: WBC elevation in patients with suspected acute appendicitis is an important parameter supporting the diagnosis at initial admission, whereas IL-6 is a more valuable tool in diagnosing advanced appendicitis.     

MSCT在无典型临床表现阑尾炎诊断中的应用

目的探讨MSCT扫描在临床表现不典型阑尾炎诊断中的价值。方法回顾性分析64例特殊类型阑尾炎的临床表现、CT扫描特征和手术资料。结果 64例经手术、病理证实的急性阑尾炎中,CT诊断与手术相符者57例,诊断符合率89.0%。CT扫描诊断为解剖异常阑尾23例（36.0%）（盆腔阑尾7例,腹膜后位阑尾10例,肝下阑尾6例）;小儿急性阑尾炎15例（23.0%）;老年人急性阑尾炎26例（41.0%）。结论 MSCT扫描对临床表现不典型阑尾炎的诊断,具有较高的临床价值。     

B型超声波用于阑尾炎诊断的临床价值探讨

目的：探讨Ｂ型超声波用于急性阑尾炎诊断的临床价值。方法：应用Ｂ型超声波诊断仪诊断各型阑尾炎，从其诊断标准、影像特点及各种频率探头的使用等方面进行了研究。结果：Ｂ型超声波对阑尾炎诊断的敏感性为８０％～８９％，特异性为８９％～９５％，准确性为９０％～９６％。结论：采用Ｂ超对某些阑尾炎的诊断简单安全、无损伤、准确率高，值得推广应用。     

Serum amyloid A protein levels as a possible aid in the diagnosis of acute appendicitis in children.

Hematological and biochemical tests, including white blood cell count (WBC), C-reactive protein (CRP) and other acute-phase reactants, have been used in the diagnosis of acute appendicitis. However, there is controversy among physicians about the value of this practice in children. The objective of our study was to evaluate serum amyloid A protein (SAA) levels in children with confirmed acute appendicitis and to compare the sensitivity and specificity of this marker of inflammation with those for WBC and CRP. A prospective cohort study of 60 children admitted with abdominal pain to rule out appendicitis was used in the study. Of these, 42 underwent surgery, while 18 children who had spontaneous amelioration within 24 h of admission were not operated on and served as controls. WBC and serum SAA and CRP levels were obtained preoperatively. Serum concentrations of the analytes were determined with particle-enhanced immunonephelometric methods. Patients with acute appendicitis had WBC, SAA and CRP levels higher than those of the control group (p<0.001). There was no appendicitis patient with a normal SAA value, while 21.4% of the patients had CRP values within the normal range. The performance of each test was measured by receiver-operating characteristic curves. Area under the curve (AUC) values were 0.849 for WBC, 0.868 for CRP and 0.964 for SAA. The sensitivity and specificity of these methods were 76% and 75% for WBC>10.0 x 10(9) /L, 62% and 94% for CRP>10 mg/L and 86% and 83% for SAA >45.0 mg/L, respectively. Circulating SAA levels have better discriminatory value than WBC or CRP in the assessment of acute appendicitis in children. Thus, this test appears to be of higher value than the current standards of care in the diagnosis of this condition.     

超声诊断急性阑尾炎的再认识

目的：探讨超声诊断急性阑尾炎的应用价值。方法：对405例急性阑尾炎患者声像图进行回顾性分析,并与手术及病理结果对照分析。结果：急性阑尾炎超声诊断准确率为91.4%,其中急性单纯性阑尾炎为82.4%,急性化脓性阑尾炎为98.6%,急性坏疽性阑尾炎为86.9%。结论：超声对急性阑尾炎的诊断有较高的实用价值。     

Integrated clinical-ultrasonographic diagnosis in acute appendicitis

PurposeAcute appendicitis is one of the commonest diseases encountered in the field of emergency surgery. If untreated, it can rapidly develop severe complications such as perforation and peritonitis. Surgeons therefore often choose early surgical treatment also when the diagnosis is only probable, facing the risk of performing an elevated amount of unnecessary appendectomies. The aim of this study is to analyse our experience with integrated clinical-ultrasonographic diagnosis in acute appendicitis.Material and methodsFrom January 1999 to December 2006, 1447 patients underwent clinical examination, leucocyte count, evaluation of C-reactive protein level, and abdominal ultrasonography using graded compression technique and a high frequency probe.ResultsIn 368 patients (25%) ultrasonographic diagnosis was acute appendicitis; 8 patients were operated on the basis of clinical evaluation only. Ultrasonography yielded false positive results in 7 cases. In 1079 patients (75%) diagnosis was negative for acute appendicitis; 173 of these patients (12%) received a different diagnosis. The remaining 906 patients underwent clinical follow-up until the symptoms disappeared; there were no complications. In our study, sensitivity of ultrasonography was 98%, specificity 99%, positive predictive value 98%, and negative predictive value 99%. Overall diagnostic accuracy was 99%.ConclusionIntegrated diagnosis of acute appendicitis based on clinical evaluation, laboratory tests and ultrasonography is safe and saves resources by preventing unnecessary operations.